Power Supply：DC 7.4V 2600mAh rechargeable lithium batteryMeasuring Method：Earth Resistance: rated current change-pole method, measurement current 20mA Max, Soil Resistivity: Wenner 4-pole measurement, Earth Voltage: average rectification(between P(S)-ES)Test Frequency：128Hz/111Hz/105Hz/94Hz(AFC)Test Voltage Wave：Sine waveShort-circuit Test Current：AC 20mA maxOpen-circuit Test Current：AC 40V maxData Storage：300setsData Hold：Data hold function: “HOLD” symbol displayData Access：Data read function: “READ” symbol displayOverflow Display：Exceeding measuring range overflow function: “OL” symbol displayLCD Dimension：LCD Frame Dimension: 128mm×75mm; LCD Display Dimension:124mm×67mmTester Dimension：280mm(L)×260mm(W)×160mm(H)Weight：Total Weight:4765kg(with package)Testing Wires：Six wires: each for Red 20m, black 20m, yellow 10m, green 10m, red 1.6m, black 1.6mAuxiliary Earth Rod：4PCS:φ10mm×150mmUSB interface：USB interface,software supervision, storage data can be uploaded to computer, saved and printed;data transmission line length:1.5mAlarm Function：Measuring value exceeds alarm setting value, will "Toot-toot-toot" alarm hintAuto Power-off：15 Minutes after power on, will outage and automatic power offOverload Protection：Measuring earth resistance: between each interfaces of C(H)-E,P(S)-ES, AC 280V/3 secondsInterference Test：Automatic recognition of interference signal , interference voltage higher than 5V will display “NOISE” symbolAuxiliary Grounding Test：Auxiliary earth resistance test function: 0.00kΩ~30kΩ(100R+rC<;50kΩ,100R+rP<;50kΩ)Protection Level：IP65(close the case status)Battery Voltage：While battery voltage decreases to around 7.8V, will display battery voltage low symbol and reminding to replace the batteryWorking current：S